Marcellus is the President and CEO of Black Fox, a hybrid enterprise information security and emergency management solutions firm based in Columbia, Maryland. Black Fox helps private, nonprofit and public organizations protect their business infrastructure from internal and external threats through resiliency and security.

Prior to launching Black Fox, Marcellus was an Information Technology Program Manager for the Federal Emergency Management Agency and he was a United States Army Special Operations Command Senior Leader, earning the John F. Kennedy Leadership Award, Bronze Star Medal and receiving the Department of Defense Purple Heart Medal.